On the afternoon of July 1, 1981, Los Angeles police responded to a distress call at 8763 Wonderland Avenue, in Laurel Canyon and discovered a grisly quadruple homicide. Ron Launius (Lucas), Billy Deverell (Nelson), Barbara Richardson (Wagner) and Joy Miller (Garofalo) were found brutally murdered, bludgeoned to death with a pipe. Launius's wife, Susan (Applegate), was left in critical condition. The police investigation that followed--led by detectives Sam Nico (Levine), Louis Cruz (Frankie G. ), and Mike Peters (Gainey), would unearth a seedy world of drugs and violence, ultimately revealing a motley crew from L. A. 's underbelly. It included ex-con David Lind (McDermott), nightclub impresario Eddie Nash (Bogosian), and porn legend John Holmes (Kilmer), as well as Holmes's estranged wife Sharon (Kudrow), and his teenage lover Dawn Schiller (Bosworth).